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KT Corporation WiBro Network, Seoul

Key Data

KT Corporation is one of Korea’s leading telecommunications companies, which provides services to residential and business users across South Korea.

The company offers fixed-line telephone services, business and data communication services including broadband internet access and leased-line, mobile services through KTF, one of its subsidiaries (previously KT Freetel), which is the second largest mobile provider.

Other telecommunications services provided include system and network integration, as well as satellite communications. The corporation owns two satellites, all of South Korea’s domestic public exchanges, the complete network of local telephone lines, public long-distance telephone transmission facilities and the primary data communications network in the country.

"The latest innovation the company has introduced is mobile WiMAX coverage."

The latest innovation the company has introduced is mobile WiMAX coverage; the company started a trial of the technology across Seoul in the first quarter of 2006.

WiBro got off the ground at some high-demand areas in Seoul and the city’s outskirts, including Sinchon, Gangnam-gu, Seocho-gu, Songpa-gu, Bundang and along the Bundang subway line.

Although the trial service has attracted few users (less than 1,000 due to lack of access devices) in April 2007 they decided to expand the network to cover the whole of the city.


WiMAX is about to be widely adopted across the world and will bring communication into previously uneconomical areas. WiMAX stands for ‘Worldwide Interoperability for Microwave Access’ and this was defined by the WiMAX Forum that formed in June 2001 to promote conformance and interoperability of the technology (IEEE 802.16), which is known officially as WirelessMAN.

WiMAX can transmit wireless data over long distances, in a number of different ways, from point to point links to full mobile cellular type access. Data rates could be in excess of 10Mbps over a short range of 2km in line of sight but ideal conditions outside of cities could allow faster speeds.

It has been recognised that the technology may be able to serve as a high bandwidth ‘backhaul’ for internet or mobile phone traffic from remote areas back to an internet backbone.

Given the limited wired infrastructure in most developing countries, the costs to install a WiMAX station in conjunction with existing mobile towers or even as a solitary hub will be small in comparison to developing a wired solution.

Areas of low population density and flat terrain are particularly suited to WiMAX and its range. WiMAX is similar to Wi-Fi, but with a much wider range and higher speed. The mobile version also allows users to move between cells with almost no interruption in signal.


KT Corp uses the Korean variant of the WiMAX standard called WiBro. Korean developers claim that WiBro and WiMAX devices and networks are already interoperable, and will be fully compatible by 2008 given suitable driver software and firmware. The developers of the electronics for the systems, Intel and LG Electronics, have already agreed on interoperability between WiBro and WiMAX as far back as 2004.

A competing WiMAX hardware developer, Nortel, has insisted that mobile WiMAX and WiBro are not compatible. Korean developers have said that WiBro transmitters in the city have a range of about 1km, and can provide internet connections at between 1–3Mbps to users travelling in vehicles at up to 120kph. The Seoul WiBro network also covers subway lines and stations.

The popularity of WiBro must be catching on as Samsung Electronics Co Ltd was given a contract in November 2005 to supply a high-speed wireless broadband network based on the WiBro standard to TVA Sistema de Televisao SA in Brazil.


"Korean developers claim that WiBro and WiMAX devices and networks are already interoperable, and will be fully compatible by 2008."

Currently the service is only accessible through a special PC card for notebook PCs. However, hardware makers such as Samsung have already developed WiBro-compatible mobile phones and other handheld devices including smartphones, laptops, PMPs and compatible USBs, including a digital multimedia broadcasting mobile TV platform, which KT Corporation will begin to market in mid-2007.

A WiBro VoIP (voice over internet protocol) service is possible and would offer a cheaper alternative to mobile phone networks for voice communications but no VoIP applications have been announced yet.

There are three competing licensed WiMAX operators in the Korean market and only two have built networks so far; the third may have a wait and see policy and will drop out on the basis of what happens to the other two.

It has been forecast that WiMAX operators will be collecting revenues of $8bn per year from 31.4 million subscribers in the Asia-Pacific region by 2012 and that spending on WiMAX networks will approach $2.9bn in five years.